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this word is used to describe water quality. This indicates that the water quality in question is in compliance with federal water quality standards developed by the United States Environmental Protection Agency.

detection limit

the minimum concentrations that must be accurately and precisely measured by the laboratory and/or specified in the quality assurance plan.

dose

the amount of contamination absorbed or deposited in the body of an exposed organism for an increment of time. A total dose is the sum of doses received by a person from a contaminant in a given interval resulting from interaction with all environmental media that contain the contaminant. Units of dose and total dose are often converted to units of mass per volume of physiological fluid or mass of tissue.

exposure

an event that occurs when there is contact at a boundary between a human being and the environment with a contaminant for a specific concentration for an interval of time: the units of exposure are concentration multiplied by time.

exposure pathway

the process by which an individual is exposed to contaminants that originate from some source of contamination and are categorized as inhalation, dermal, and/or ingestion exposures.

gene mutation

a persistent change in a single gene.

latency

the period between stimulus application and response onset.

maximum contaminant levels

enforceable drinking water standards that are protective of public health to the extent feasible with current technology.

minimal risk level

an estimate of daily exposure of a human being to a chemical (in mg/kg/day) that is likely to be without an appreciable risk of adverse noncancerous effects over a specified duration of exposure.